Pneumatic tool



(No Model.)

W. M. WOOD. PNEUMATIG T001..

No. 443,029. Patented Deo. 16, 1890i.

UNTTED i STATES PATENT EErcE.

WILLIAM M. VOOD, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR TO THE THOMSON ELECTRIC WELDING COMPANY, OE MAINE.

PNEUMATIC TOOL.

SPECIFICATION forming part of Letters Patent No. 443,029, dated December 16, 1890.

Application tiled March 28, 1890. Serial No. 345,766. (No model.)

To @ZZ whom it may con/cern: Referring to Fig. l, II I-I II indicate three Be it known that I, VILLIAM M. IVOOD, a plungers or pistons Workingin cylinders and. citizen of the United States, and a resident adapted to be reciprocated by iiuid-pressure of XVaShingtOn, in the District of Columbia, applied alternately at opposite sides of the 55 5 haveinventedacertain new and useful Pneupiston through chambers er passages t' l.y matic Tool, of which the following is a speci- The plungers H carry hammers or other tools iication. Y II2 and operate on radial lines converging or My invention relates to pneumatic tools of meeting in the work, such as a piece of metal the class in which hammers, dies, swages, Wto be hammered or to have a burr upon 6o [o cutters, or other instruments are operated by its exterior reduced. The passages i' fr' allV rapidly-repeated movements of a piston or connect with a port, as m, to be presently deplunger actuated by the pressure of air, gas, scribed, through which the air, gas., steam, steam, or other fluid under pressure. or other iiuid under pressure is delivered My invention is designed particularly for through the passages and to the cylinders at 65 r 5 usein instruments employed forreducingthe one side of the pistons, while the passages Z burr or expansion at the weld formed beconnect with a similar port n, for delivering tween two pieces of metal by the ordinary air or other gas or fluid underpressure to the process ot elect-ric welding,in which end pressopposite side of the piston. The pressure at ure is employed, though the novel fea-tures ports in 'n is controlled by a valve-movement, 70 ze of construction and combinations ot' devices as will be presently described. Instead of a hereinafter described and claimed are many valve controlling` the admission of air, gas, of them useful in pneumatic tools generally. steam, or otheriiuid under pressure any other One ot' the objects of my invention is to means might be used for producing pressure provide a simple and effective instrument at opposite sides of the pistons H alternately. 7 5 2 5 which may be used in reducing the burr at In the preferred form of my invention the an electrically-formed weld by means of rapports m n serve also as the exhaust-ports. idly-delivered blows from two or more ham- The plungers H maybe cushioned on their mers or dies.v back throw by means of projections H3 from Another object of my invention is to prothe cylinder-heads, which projections are. 8o 3o vide a simple and elfe-ctive controlling-valve adapted to iit into air cups or cavities in the whereby the action of the gas or fluid under piston-heads or plungers, as indicated. pressure in operating the hammers or other By using the three hammers placed radi` instruments may be controlled. ally, as shown, at distances one hundred and My invention consists in the combinations twenty degrees apart a revolution of the tool 85l 3 5 of parts and details of construction hereinone-third the circumference of the work willv after described in connection with the accomcover the whole surface to be operated upon.` panying drawings. For the purpose ot' adjusting the hammers My invention consists, also, in the novel for different-sized worleso that they shall be combination of two reciprocating pistons, normally equidistant from the center, I pro- 9o 4o which may act as the valvemo\f'ement for vide a slide, guide, or gage I, fixed to the controlling the fluid-pressure upon the pistons stock or castingr unitingthe cylinders forplunor plungers carrying the tools or may be gers H and adapted to engage with the work, used for actuating a tool directly. as indicated. As the hammers or tools H2 Inv the accompanying drawings, Figure l is are operated by independent plungers, their 95 45 a vertical central section throughan apparat us stroke may be proportionately greator short,

embodying my invention. Fig. 2 is a veraccording to the work they are operating tical longitudinal section and partial side eleupon, of course within the limitations of the vation ot' another form of my invention, and capacity of a tool. Hence not only is the shows the application of the automatic valvep tool well adapted to different sizes of worl, roo 5o movement t-o the operation of a hammer or but oval or irregular work may be readily die directly. hammered or operated upon, one hammer making a short st1oke,wl1ilc the others make longer ones.

The handle K, connected to the tool in any suitable manner, serves to move the same around the work. The air, gas, steam, or other fluid under pressure may be supplied through a flexible tube K2, so that the t'ree movement of the tool by hand may not be interfered with.

rlhe cylinders for the several plungers may be formed in a common casting, in which the passages Z i are also formed by casting, or the cylinders might be separately vformed and mounted and connected with a comm on source of pressure through pipes or passages in any other desired manner.

An automat-ic valve-movement suitable for producing the desired pressure and exhaust for plungers ll H maybe made as follows:

A A is a double-acting piston working in a suitable chamber, as shown, and kept in op` eration by air or fluid pressure admitted alternatelyat opposite ends of the cylinder through the ports a. a. The piston-heads A are connected by a rod C, thus leaving` a pressurespace, which is put in communication by the reciprocation ot the piston alternately with the ports b b. Air or gas under pressure is delivered to the space between the piston-heads through a port or opening c, which communicates by a pipe leading through the handle K with the tube K2. Suitable stops are provided for the double piston A at the ends of the cylinder in which it works, and by suitable construction the piston may be cushioned at the end ot' a stroke by confining the air or gas under pressure in cavities or cups upon the piston-heads, which slip over projections on the cylinder-heads at the end of a stroke.

B Bis a second double-acting piston, which is kept in operation by airor gas pressure admitted alternately through ports Z1 Z/ to spaces at the inside ot the piston-heads. The piston-heads are connected by a rod, as shown, workingl through a diaphragm, and the connecting-rod may have a packing at t-he point where it passes through the diaphragm, if desired, although this is not absolutely necessary, since a slight amount of leakage from one side to the other will not prevent the operation of the apparatus. Piston-heads B B alternately cover and uncover the ports a a for admission of the air or gas under pressure to the cylinder in which the piston A works. This air or gas pressure is conveniently and preferably taken from the part of the cylinder for piston B B wherein the pressure exists for operating the latter. Piston B B may be cushioned at the end of each stroke by allowing the piston-heads to confine a small volume of air between the head and the diaphragm in obvious manner, and the cushioning action may be assisted by means of springs applied as shown should it be deemed desirable. rlhese springs may also aid in reversing the movement of the piston. The

cylinders for the two pistons are preferably formed in the same casting and are parallel with one another. The outerends ot the cylinders for the double piston B are left open to the outer air or to an exhaust-chamber, so that ports a a', when uncovered by a movement of their piston B toward the central diaphragm, may form exhaust-ports for the cylinder in which the piston A works.

To make the operation of the two pistons A A B B, in the manner to be presently described, control the action of the plungers Il II, it is simply necessary to put the ports in n. in permanent connection with the spaces at the inner sides ot the heads B B. The inlet and exhaust for the air or gas under pressure to the plungers H might be controlled by the movementot' the pistons B B in any other desired way, though the arrangement shown is the preferable one. The movement of the pistons B B might also, as will be presently shown, instead of controlling the action of the air or gas for the purpose of operating the tool, actuate the tool itself directly and mechanically, or said piston might carry the tool itself in some forms of instruments, as will be presently described.

The operation of the valve or piston movement composed of the two pistons A A B B is as follows: In the position of the pistons shown the air passes by port Z) and port a to one side ot piston A, the space at the opposite side of piston A being` open through the port a' to the exhaust. Thepiston A is thereupon moved to the right with the effect of shutting oft' the air-pressure at port b from piston B and opening the port b for communication with the source of air-pressure. At the same time the movement of the piston A is sufiicient to open communication by port?) with the space at the left-hand end of the cylinder for A, so that the air or gas may exhaust from the pressure-space at the left end of the double piston B as soon as said piston B moves slightly to the right and opens the port a at the rear side ot the piston-head B. Piston B now moves to the right until,iinally, it opens communication by way of port d between the space at the inside of the righthand piston B and the right-hand end of piston A to produce reverse movement, the eX- haust at the opposite end of piston A taking place now through port d. Piston A byits reverse movement opens the port b for ad mission of air or gas under pressure to cause movement of piston B to the left, the exhaust for such piston B now taking place through port Z1', which has been uncovered by the movement of A to the left, so that the exhaust may pass through the cylinder of A and outby port a. The reversal of movement of the large piston B at each stroke is assisted by the spring as well as by the fact that the piston A, after covering port b or Zi and so as to shut oft the air-pressure from b and open the port Z) or h as an exhaust, will, on continuation of its movement, produce rarcfaction oi' the air or IOO IIO

IZO

gas which might be confined in the position of the piston B shown, thereby causing an inequality of the pressures tending to move the piston B after communication is established by way of port b to the space at the inside of. the right-hand piston-head B. It will be obvious that as the ports m n communicate with the spaces between the pistonheads B and the diaphragm C2, where pressure and exhaust take place alternately, there will be in the passages t Zand in the spaces at the opposite sides ot' the plungers H H H a condition of alternate pressure and exhaust or lowering of pressure, which will cause said plungers to reciprocate with the piston B. Thus when there is pressure in the space between one of the piston-heads B and the intermediate diaphragm `tending to move said piston in one direction-as, for instance7 in the space communicating by port n with the passages Z-there will be at the same time exhaust-passages opened for the escape of the steam or other fluid under pressure from the space between the inner side of the other piston head B and the intermediate diaphragm, so that the pressure in the passages i, communicating with port m, may be relieved. Under this condition the pistons H will move back away from the work through the pressure communicated through n and passages l, the exhaust taking place through 't' and m, b', and a. lllhen, however, the valve mechanism moves in the opposite direction through the pressure communicated to the space between the head B and the intermediate diaphragm, with which space port m communicates, there will be, as before described, an exhaust for the air, gas, steam, or other fluid under pressure in the space with which the port n communicates, so that under this condition of affairs pressure will now be communicated lthrough m and passages z' to the rear of the plungers I-l, while an exhaust will exist through the passages Z, the port n, and the ports b c.

It will be observed that the ports b b are pressure and exhaust ports for the doubleacting piston B and are controlled by the action of the double acting piston A A, so as to produce reciprocation of the piston B, while in the same manner the ports a 0, are alternately inlet and exhaust ports for piston A and are controlled by the movements of B. Each piston operates, therefore, as a valve for controlling the inlet and exhaust of the other by means of two sets of ports a a h h', and each piston moves in its own cylinder and is not, as in some previous constructions, carried by the other. It will be seen that the organization is extremely simple, and in practice I find that a perfectly automatic motion of great rapidity and absolute certainty is Vobtained whether such piston, or the valvemovement of one of said pistons, be applied to controlling admission of air or gas under pressure to otherv pistons or plungers, or whether the movement of one of said pistons be employed to actuate directly or indirectly any suitable tool. l

By operating the tool by means of plungers H independent of the valve-movement I obtain the advantage that the stroke of the plunger carrying the tool may be variable and is entirely independent of the movement of the automatic piston-valves, where there is practically a fixed length of stroke.

It will be observed that by simply connecting the cylinders for the plungers H H with spaces or chambers of the automatic valvemovement where there is alternately a pressure and exhaust in the operation of such valve-movement I obtain the maximum of simplicity in the operation of a separate set of plun gers carrying the tools by the controlling action of one of the pistons of the automatic valve-movement.

At A3 is indicated a stop or catch adapted to engage with one of the valves of the piston-valve movement, so as to hold the parts in the position shown, where the air-pressure will be applied to the pistons or plungers Hin a manner to hold the same raised away from the work and ready for use. lVhen it is desired to start the tool into operation, the stop A3 is removed by means of a lever applied in con` venient position on the handle K, as showin In Fig. 2 I'have shown the applicationof the automatic valve-movement to the operation of a striker or hammer which actuates a tool-carrying bar or spindle. Here one of the sets of pistons, as B B, carries the striker, as`

M,whieh operates on a tool-carrying spindle N. Two separate hammers or strikers are provided, operating on straight lines meeting in the Work, which is represented at W as a bar or piece of metal subjected to the action of two swages S S, carried by the spindles or rods N N. The valve-movements and parts supporting the swages at each end ot' the machine are mounted on a suitable base-plate or support T, which slides on a frame 0r table. By means of a right and left hand screw lP, applied as shown to the moving parts, the valve mechanisms, with the corresponding swages, may be caused to open or close at will. When operating on a piece of hot metal which has y just been welded, as in an electric weldingmachine, the strikers or hammers may be kept running all the time, and the swages gradually drawn in toward the work by a turn or two of the feed-screw as the work is reduced in size. Then the hammering is finished, it is only necessary to reverse the feed far enough to move cach hammer half the diameter of the work in order to remove it. In this arrangement the small piston-valve is placed underneath the two open cylinders which contain the main pistons, and the air is brought into a port which passes down one side and en ters at the middle. In place of the swages S S other tools operating on the work might be employed, as is obvious.

While I have described the use of a'right and left hand screw for moving the two parts IOO IlO

of the apparatus, l `ig. 2, at opposite sides oi' the work, I do not limit myself to such dcvice, as any other mechanical movement adapted to produce the motion described will obviously answer' the purposes when properly connected to the slides carrying the pneumatic tool.

lVhat I claim as my invention isl. The combination, in a pneumatic tool, of two or more plunger-s operating on lines meeting ata common point or center and each bearing or actuating a hammer or equivalent device, as described, a source of air, gas, steam, or other fluid under pressure, and a valve com m on to said plun gers for controlling the passage of the steam or other fluid, so as to operate the plungers simultaneously.

2. In a pneumatic tool, the combination, with two actuating-plungers Operating on converging or meeting lines, of a valve-movement independent ot' the motion et' the plungers for controlling the air, gas, steam, or other fluid pressure which actuates them.

3. The combination, with the three hammer or die carryiire,` plungers working on converging lines, of a stop or gagcadaptcd te rest on the work for adjusting the hammers or tools to different sizes of work, as and Vfor the purpose described.

4t. The combination, with the tool-actuating plunger, ot a valve-movement controlling the air, gas, steam, or other fluid pressure that actuates such plunger, and a catch for engaging with the valve-movement, so as to hold the same in position to permit the air or fluid pressure to keep the plunger lifted.

5. In a pneumatic tool, three or more plungers working on converging lines and each carrying a hammer or die at its inner side, and a flexible pipe or connection K9, t'or conveying air, gas, steam, or other fluid under pressure to operate said plunger-s and to permit the same to be moved circumi'erentially around the work.

(5. The combination, with the tool-carrying plunger, of the two reciprocatory pistonvalves, each controlling in its movement the exhaust and inlet for the other, so as to keep the said pistons or valves in continued movement while air, gas, steam, or other fluid under pressure is supplied to them,and connections from opposite sides et the said tool-carrying plunger to chambers or spaces of the valve system where pressure and exhaust exist alternately, as and f'or the purpose described.

7. In a pneumatic tool, three tooleearrying plungers ll II Il, working on lines converging` toward a com mon center and all having pipes or passages leadingfrom opposite sides ot the plungers and connecting` each with a common source of air, gas, steam,or other fluid under pressure.

S. The combination,in a pneumatic tool,ot two or more plungers working' toward and from a common center, a hammer cr other tool carried by each and adapted to engage with the work directly, a source of air, gas, steam, or other fluid under pressure common to said plungers, and an automatic valve mechanism operated by the pressure of the fluid and controlling` the controlling-ports leading to the plringer-cylinders.

9. IIhe combination, with the parallel double-acting pistons, ot two pairs of port-s connecting the chambers in which said pistons reciprocate, each pair being controlled by one ot' said pistons and forming alternately inlet and exhaust ports for the other.

l0. The combination, substantially as de scribed, of a piston B 3, and a piston A,eontrol ling the inlet-ports, whereby air, gas, steam, or other fluid is admitted to aetuate the pistons B and ports a a', which are alternately covered and uncovered by piston B, so as to admit air or gas under pressure to opposite sides of piston A alternately.

ll. The combination, substantially as described, ot a double-acting piston A, actuated by pressure applied upon its opposite ends alternately, a piston l5 B, actuated by pressure applied alternately through ports controlled by the piston A, and ports or openings which are alternately uncovered by the piston l, se as to place such ports in communication with the pressure spaces or chambers et piston B, so as to admit Huid under pressure for the operation of piston A.

l2. The combination, substantially as described, ot two parallel pistons A l5, having their chambers connected by lateral ports with which said pistons coact, as described, so as to each control the exhaust and inlet of the other, as and for the purpose described.

13. The combimttion, substantially as described, of two reciprocatory double-acting pistons, ports or passages b 1)', placed in commnnication alternately by one of said pistons with a source et air, gas, steam, or other Huid under pressure and leading to the pressurespaces for actuating the second piston, and ports orpassages, as d a', communicating with the pressurespaces ot the First piston and alternatel y connected with the pressure-spaces of the second piston by movement ot the latter.

li. The combination of the double-acting piston B B, having heads connected by a rod passing through a diaphragm and working in cylinders or chambers open at their outer ends, a piston A A, working in a chamber closed at its outer ends, ports l; b', controlled by the piston A and forming alternately inlet and exhaust ports for the piston B B, and ports a a', controlled by piston B B and forming alternately inlet and exhaust ports for the piston A A as well as part of the exhaustpassages for the piston B D.

15. In a pneumatic tool, the combination, with shaping tools or instruments operating in the same line and on opposite sides of the work, ot' adjustable supports for each tool and means for moving said tools to and from one another simultaneously.

IOO

IIO

mounted on an adjustable support, and swaging or forming tool S, mounted on an adjustable support at the opposite side of the work, and means for moving` the two swages or forming-instruments away from or toward the Work simultaneously.

Signed at Boston, in the county of Suffolk and State of Massachusetts, this Qtth'day of March, A. D. 1890.

WILLIAM M. VlDOD.

Titnessem HENRY N. SWEET, II, PERCY MAXIM. 

